Method for generating a component by a power-bed-based additive manufacturing method and powder for use in such a method

Abstract

The disclosure relates to a powder and a method for generating a component by a powder-bed-based additive manufacturing method, such as laser melting. The powder includes particles having a core and a shell. The particles have an alloy composition of the component. The concentration of higher-melting alloy elements is greater in the shell and the concentration of lower-melting alloy elements is greater in the core, wherein the surface of the particles is higher in comparison with particles with a constant alloy composition. This advantageously prevents the particles from caking together in the powder bed during the production of the component, and so the powder bed may also be subjected to high preheating temperatures of up to 1000° C.

Description

[0001]The present patent document is a § 371 nationalization of PCT Application Serial No. PCT / EP2017 / 071725, filed Aug. 30, 2017, designating the United States, which is hereby incorporated by reference, and this patent document also claims the benefit of German Patent Application No. DE 10 2016 216 859.2, filed Sep. 6, 2016, which is also hereby incorporated by reference.TECHNICAL FIELD[0002]The disclosure relates to a method for generating a component, (e.g., composed of a superalloy), by a powder-bed-based additive production method. With this method, the component is built up layer by layer in a powder bed by the melting of particles forming the powder bed by an energy beam such as, for example, an electron beam or a laser beam. In this case, the powder bed is preheated to a temperature below the melting temperature of the particles, before and while the particles are melted. The disclosure further relates to a powder suitable for use in a powder-bed-based additive production m...

AI Technical Summary

Benefits of technology

The patent text describes a method for producing powdered metal alloy particles with a desired composition. The method involves creating particles with a core and shell, where the shell is made up of a single metallic alloy element. The alloy composition of the particles is determined by the alloy composition of the core and shell. The method also involves melting or sintering the powder to form the desired alloy composition. The technical effect of this method is that the alloy composition of the particles is controlled, and the particles have improved properties such as better caking resistance and easier production of complex structures.

Problems solved by technology

In this case, however, the problem occurs that the products produced are subject to high inherent stresses, and that cracks may occur because of this fact.

This gives rise to the problem, in the case of selective laser melting, that the powder bed solidifies and may also stick to the surface of the component produced.

Cleanly removing the component produced from the powder bed is then no longer possible.

Moreover, the powder cannot be reused if the particles undergo caking to one another.

This makes the method more expensive, because raw material regularly has to be discarded.

The caking / sticking of the powder bed may additionally lead to an uneven surface of the powder bed.

This complicates the application of further powder layers, and may give rise to geometric defects in the surface of the powder bed.

As a result, the quality of the components under production is impaired.

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